Fighter jets bombed Taliban hide-outs in Pakistan's troubled northwest while troops pushed into militant territory on the ground, killing at least 40 insurgents in a 24-hour siege, the army said.

Separately, five others died when an explosion ripped through a house near the Afghan border, local officials said on Saturday. Claims that it was a missile strike could not immediately be confirmed. Pakistan's five-month-old civilian government has been plagued by violence and political instability since Pervez Musharraf was forced to resign as president two weeks ago, adding to the many challenges ahead in the Muslim nation of 160 million people. But with a string of suicide bombings, including one that left 67 dead near the capital, tackling extremism is a priority. Leaders initially offered to hold peace talks with insurgents something Musharraf also briefly tried before his ouster but have since resorted to what some are calling all-out war. Army spokesman Maj. Nasir Ali said at least 40 Taliban were killed on Friday when fighter jets pounded militants in Swat Valley, which was a popular tourist destination not long ago. A cache of ammunition exploded when it was hit in one of the strikes, he said, adding ground troops were advancing into the region on Saturday to root out other militant fighters. Taliban spokesman Muslim Khan said eight of his men, including a local commander, were killed.

The violence followed news that Asif Ali Zardari, who seems poised to be voted Pakistan's next president in a Sept. 6 election by lawmakers, had moved into a tightly guarded government compound because of security fears.

His late wife, Benazir Bhutto, a two-time former prime minister and an outspoken critic of Islamic extremism, was assassinated in a Dec. 27 gun-and-bomb attack during a campaign rally. Officials say that fighting in Swat and Bajur have left nearly 500 militants dead in August alone. There are no separate statistics for civilians, but witnesses say dozens have died. More than 200,000 others have been forced to flee their homes, most of them women and children, and are now living in desperate conditions in sweltering, mosquito-infested relief camps. Human rights groups expressed concern on Saturday about the rising violence.

Locals "insist there is no targeted operation against militants, rather it is a haphazard armed invasion on the people of Swat," Asma Jahangir, chairwoman of the Human Rights Commission of Pakistan, wrote in a letter to the prime minister.